The Conservatives will "almost certainly" lose control of Guildford Borough Council due to government policy, the local authority's leader has warned David Cameron.

In a letter to the prime minister, Councillor Stephen Mansbridge said the council was being forced to make decisions about the green belt which would also put Tory MP Anne Milton’s Guildford seat in jeopardy.

The broadside was sent on February 21 and has been seen by the Surrey Advertiser.

Strong opposition has been met from villagers over the possibility of insetting settlements from the green belt and allowing large-scale developments in the countryside.

Cllr Mansbridge wrote about the "impossible electoral position" the government’s policies were putting the council’s Conservative group in.

He said: "We are being controlled at every turn: through the cap on council tax; the anticipated erosion of the Settlement Grant forcing a position to build an excessive number of new homes, even on our green belt, in order to gain the New Homes Bonus; we are being told that we will not be eligible for LEP [Local Enterprise Partnership] funding unless we over-deliver on housing; we are being instructed how to conduct our voting in council meetings; and, worst of all, we are being placed in a position over the green belt that will jeopardise the seat of our MP, Anne Milton, and almost certainly see our council go out of Conservative control for the first time in 12 years."

Cllr Mansbridge went on to note that whole branches of the local Conservative Association had party members deserting and that UKIP won more than 20% of the vote in the county elections last year.

“Immigration, the EU [European Union] and gay marriage are frequently given as reasons for this,” he wrote.

The UK Independence Party took one of the county council seats in a Guildford division last May, with George Johnson winning in Shalford after an administrative error meant the Conservative incumbent, Simon Gimson, was not registered to stand.

“We understand the need to build more homes and we are prepared to take difficult decisions in order to achieve this, but you have largely removed our ability to choose how we accomplish this task and keep our electorate on side," Cllr Mansbridge complained in the letter to Mr Cameron.

"I have met with Nick Boles to discuss our Local Plan and with Robert Goodwill to discuss our acute traffic congestion and I have little confidence that anything truly constructive will emerge as a result.

“We are normally a very positive, forward-looking council with a vibrant local economy, where Surrey contributes more to the Treasury than anywhere apart from London , but that now is being curtailed by the lack of infrastructure funding.

"I realise that you are unlikely to visit us, as you turned down the invitation by Surrey leaders last year, so from a distance I urge you, indeed implore you, to have a deep rethink before this situation becomes irreversible.”